In previous studies we have shown that factors released from S. purpuratus sea urchin eggs can elevate sea urchin sperm cyclic AMP levels by as much as 100-fold and can lower cyclic GMP levels by about 40%. It will be determined whether or not these factors are released from the egg itself or from the jelly coat surrounding the egg. The egg proper and the jelly coat will be separated by the use of acidified sea water. The cyclic AMP-elevating factors will be purified by ion-exchange chromatography, adsorption chromatography, gel filtration, and by other methods, and characterized biochemically. The purified factor(s) will be tested for effects on sea urchin sperm motility, metabolism and membrane structure, and these effects will be correlated with changes in the sperm cyclic nucleotide content. The purified factors will also be tested for effects on mammalian sperm and other mammalian tissues as well as for effects on various enzymes, including adenylate cyclase, guanylate cyclase and phosphodiesterase. The effects on the enzymes will be studied in both intact and broken cell preparations. Finally, a search will be made for similar types of factors in eggs from other species.